[PATCH v9 03/10] sched: remove frequency scaling from cpu_capacity

Morten Rasmussen morten.rasmussen at arm.com
Fri Nov 21 04:35:26 PST 2014

On Mon, Nov 03, 2014 at 04:54:40PM +0000, Vincent Guittot wrote:
> Now that arch_scale_cpu_capacity has been introduced to scale the original
> capacity, the arch_scale_freq_capacity is no longer used (it was
> previously used by ARM arch). Remove arch_scale_freq_capacity from the
> computation of cpu_capacity. The frequency invariance will be handled in the
> load tracking and not in the CPU capacity. 

Just a note:

Yes, we are scaling the load tracking of each task to compensate for
frequency scaling. I think that is all fine. Later we will have to feed
the current frequency into the energy model as well to figure out if
putting more tasks on a cpu will/should cause the frequency to increase
or not. We don't need it for now and don't need to add it in the commit
message. It is just a reminder that we may actually want to use
arch_scale_freq_capacity() combined with cpu_capacity to provide this
input to the energy model later.

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